Prevalence of Cattle Piroplasmosis and Some Associated Risk Factors in Lower Shabelle Region, Somalia

Aamir Muse Osman1*, Kalthoum Moallim Yususf1 and Abdalla Mohamed Ibrahim2

Keywords: Babesiosis; Cattle; Somalia; Theileriosis; Tick

Introduction

Babesiosis and Theileriosis are important tick-borne diseases of Cattle worldwide including Somalia. They are caused by the protozoan parasites, Babesia and Theileria spp respectively [1]. In Somalia, Cattle Piroplasmosis is great concern since the country possesses population of Cattle that estimated at nearly 5,100,000 heads in 2013. The herd structure is comprised of 80-87% female herd with 20-30% lactating. It is estimated that the average milk production per cow is 2 litres per day with an estimated gate farm price of 1 USD [2].

Cattle Babesiosis is caused by Babesia bovis and B. bigemina and the disease is transmitted by Rhipicephalus ticks [3]. Animals suffering from acute Babesiosis can have a variety of symptoms such as fever, increased heart rate, increased respiratory rate, abnormal mucous membrane color, and low PCV values. Although these symptoms are very typical, they are not pathognomonic, and animals with chronic infections can be asymptomatic carriers [4, 5].

Cattle theileriosis is mostly cause Theileria annulata and Theileria parva [6]. They are transmitted by ixodid ticks [7]. It is characterized by high fever, weakness, weight loss, conjunctival petechia, enlarged lymph nodes and anaemia [8].

B. bovis, B. bigemina, T. parva, and T. annulata cause mortalities and morbidities leading to losses in production of milk, meat, and other livestock by-products. Consequently, they cause severe economic losses to livestock farmers involved in dairy and beef production in tropical and sub- tropical regions [9]. The diagnosis of these diseases in Somalia Cattle have depend on mostly on microscopic examination of blood smears [10] and antibody detection [11, 12]. However, these studies have been limited to a few tick-borne diseases with all of the studies were lack adequate information to assess the correlation of different tick species with disease occurrence despite its significant role in disease transmission and also which is critical for the control and prevention of these diseases. Hence, there is scarcity of information on Cattle Piroplasmosis at national level and in Lower shabelle region in particular. Therefore, the present study aimed to assess the prevalence of Cattle Piroplasmosis in three districts of Somalia using microscopic detection and to identify different tick species associated with occurrence of Piroplasmosis.

Discussion

In the present study, the prevalence of Cattle Babesiosis and Theileriosis in Lower shabelle region of Somalia was 91.3% and 66.1% respectively. The prevalence of Babesiosis of this study is higher than the study reported by Caille [12]. Theileriosis prevalence was higher than that reported by Heuer, et al. [10] and Schoepf, et al. [11], and Lower then study reported by Caille [12]. The slight rise of prevalence might be resulted from continuous migration of Cattle search for better grazing. This was expected because, the large part of the grazing area available in southern part of the country or may be caused by different sampling times, sampling strategies and locations. In the current study a slightly lower prevalence rate in male cattle was recorded (87.5%), as compared to female cattle (91.6%) of Babesiosis. However, the difference in the prevalence of positivity between the two sexes of the cattle as not statistically significant (P>0.05). This is consistent with findings of previous studies that observed similar findings [14]. The reason, why in the current study it was observed that both sexes were found to be equally exposed to Babesia infection, is the fact that cattle usually graze together in the grassland and overnight in stalls. This practice is likely to facilitate the transfer of ticks within the herds and eventually, facilitated the equal distribution of ticks among cattle leading to equal exposure in both sexes [15]. While Theileriosis male Cattle (87.5%) is higher prevalence then female Cattle (64.1%) with statistically insignificant (P>0.05). This result is in agreement with the finding of the study in Uganda [16]. The reason, Male cattle were associated with a slightly higher probability of infection with Theleria than females and castrates, that may be due to a reduction in activity in the individual associated with castration and a reduction of testosterone levels in castrates [17]. They were also reported that, Lower physiological activity in females and castrates is associated with lower grazing activity resulting in a reduced probability of the animal encountering to the tick and therefore exposure to infection with Theileria.

Increasing age has been frequently reported to be associated with increased TBDs prevalence [18]. The result of this study also showed as there was a clear gradient of age effects where the risk of exposure increased with age in both infections (Theileriosis and Babesiosis). Insignificantly (P=0.761) highest prevalence of Cattle Babesiosis was recorded in 2-5 years flowed >5 years and lowest <2 year old. This result in line with the finding of studies conducted Amorim, et al. [19]. While Theileriosis, the highest prevalence was recorded 2-5 years flowed <2 years and lowest> 5 years old. This agreed by Kundave, et al. [20].

Furthermore, the high prevalence in adult animals could be due to the following reasons: Calves under the age of two years remained in paddocks close to homesteads while adults grazed away far in the field. In communal grazing areas, animal met with others from different places in which some could be infested with ticks, thus facilitating the spread of ticks from one herd to another [21]. It is a well-known fact that handling of calves for nursing is easier to farmers than handling adult animals. Therefore, it is possible that farmers in this study were able to de-tick calves rather than the adult cattle.

The PCV of individual animals is a useful indicator of anaemia which is recognized as the most important consequence of several ticks born disease including Babesiosis and Theileriosis in cattle [4]. In the present study, No statistical difference (U = 510.5, Z = − 1.05, P = 0.294) was found in mean PCV between Babesia- positive (0.27 l/l) and Babesia-negative Cattle (0.28 l/l). Similarly, No statistical difference (U = 1507.5, Z = − 1.42, P = 0.155) was found in mean PCV between Theileria- positive (0.27 l/l) and Theielria-negative Cattle (0.29 l/l). The difference in mean PCV of the two groups could be attributed to the severe haemolytic process associated the presence of piroplams inside the erythrocytes and destruction of large numbers of these erythrocytes by the parasite thereby resulting in hemoglobinaemia and consequently hemoglobinuria [20].

Various tick species such as Rhipicephalus Spp. etc. are the most likely known source for Babesia and Theileria infections in the tropics [3]. During collection of blood samples, the existence of ticks on the environment and infestation on cattle was observed; this is similar to the findings of Pegram [23].

In conclusion, this study revealed a very high prevalence of Piroplasmosis close to 100% in the study area and co- infections were more common than single infections. This might have implications for potential interactions of pathogens and the patterns of clinical symptoms. Further studies and investigation of the disease in other areas in the country should be encouraged.

Acknowledgements

The authors thank Abrar University for their support to carry out this work.

Conflict of Interest

The authors declare that they have no conflict of interest regarding the publication of this article.